Process of carbonizing coal



Patented Apr. 14, 1931 UNITED srATes KENNETH m. smrsoN, or Nnw roms;I N. r.

PROCESS OF CARBONIZIN COAL Application filed .Tune 28,

My process broadly consists in imparting to a series of moving receptacles a carbonizing heat while passing through a heating zone, and in introducing to said receptacles s pulverized carbonaceous material while mov'- ing through a cooler zone, the heat absorbed by the material constituting the receptacles being suiiicient during this later movement to vaporize out-the volatiles from the comto minuted carbonaceous material and leave a substantiaily carbonized product.

The invention also comprehends utilizing a continuous conveyor consisting of interconnected receptacles adapted to pass i through a heating zone to receive their carbonizing heat after which material is introduced to said vessels while moving through a cooler Zone, the heat absorbed by the material constitutin the vessels, being, however,

sucient to car nize the introduced charge of iinely comminuted material. lt is there-` fore apparent that no direct heat is applied to the vessels while filled with carbonaceous materials and that the low temperature carbonization occurs solely by reason of the heat contained in the vessels.

In the accompanying drawings I hav shown the referred embodiment of an apparatus capa le of supporting this process, in

which Figure l, represents a longitudinal sectional view of my apparatus; and,

Figure 2 a cross section of the same. Referring now more particularly to the drawings wherein like reference characters indicate corresponding parts, the .numeral 1 designates a furnace structure which may be formed of any desired and conventional material and which is provided with an open interior 2 adapted to receive the interposed hearth 3 constructed of brick or the like.

The bottom 4 of the furnace is formed with dues 5, these lues being adapted to conduct heating ases from the combustion chamber 5' seated eneath this wall. Gases or the like are burned in the combustion chamber by means of the burner 6 to supply the necessary heat for carrying out the process.

The furnace is provided with a top wall having a va or outlet 7 leading therefrom,

,W which exten to any suitable receiver, con- 1924. Serial No. 728,022..

denser or the like. The waste gases from the flues 5 pass into the collecting ue 8 at the side of the furnace, then up through the stackflue 9, then out the stack 10. t

Disposed within the interior 2 of the furnace l near each side of the hearth 3 I provide sprockets 7 and 8 around which an endless conveyor 9 passes, the conveyor `9 consisting of a series of metallic pans 10 carried by sprocket chains 11 extending around the sprockets 7 and 8. Thesepans l0 sub stantially abut one another and oder a continuous conveying surface. The sprockets 7 and 8 are driven by hand or any suitable power mechanism.

M It will be apparent that the iiues 5 heat the under side of the retort 2 so that the metallic pans 10 receive their maximum heat while travelling on the under side of the hearth 3 and adjacent the ilues 5. The retort near its forward end` is provided with` an outlet opening 13 which is sealed to prevent the discharge of heat from the chamber 2 and through which opening carbonized particles, coal and the like are discharged from the pans 10, as they move around the sprockets 7.

Adjacent the main conveyor 9 I provide kan 4auxiliary conveyor 14, the same consisting of a series of pans similar to the pans 10 connectedtogether by chains travelling around the ysprockets-15 and 16. The auxiliary conyveyor 14 feeds to the main conveyor 9, if this is found to. be desirable, or the main conveyor can be fed entirely independently of the auxiliary conveyor. To this end I provide a feed 16 for the auxiliary conveyor and a feed l7ffor the main conveyor. Pulveriz'ed materials, such as powdered coal, mixtures of coal and oil, and the like fill the feed hopper f16 and 17 and regulated quantities of this material can be dropped into the pans carriedv by the conveyor chains from time to time during the operation of the apparatus. It will be observed that the -pans 10 are constructed ofcast iron or similar metal which will absorb and retain sufficient quantities of heat when passing over the flues 5 to cause a low temperature carbonization of the material later introduced to said heated pans when travelling over the hearth 3. It may be necessary at times to construct the pans of unusual thlckness in order that the will retain sufficient heat to cause the car onization. It is 5 one of the salient objects of this invention to also provide an improved process for the low temperature carbonization of fuels which may be carried out in an apparatus of the character herein disclosed.

The process briey consists in subjecting a plurality of pans, vessels or the like to a temperature while they contain `no coal or other carbonaceous fuels, and after said pans have been highly heated and while moving through a cooler zone I then introduce to the pans charges of finely pulverized carbonapeous materials. The temperature of the pans is suilicient after the introduction of such materials thereto to vaporize out the volatiles contained in the fine coal particles leaving a substantially carbonized residue. In the process it is necessar that the ans possess asuiiicient quantit o metal or ot er material which will absor and retain the 'desired amount of heat to effect the carboni'zation of the coal. II have found, however, that pans constructed of relatively thick cast iron material will very satisfactorily perform this process.

In carrying out the process in the apparatus herein described, I heat the retort to a temperature well in excess of 700 C., the temperature being suiiicient, however,to heat the cast iron pans 10 to a temperature of at least y In each-pan I deposit pulverized coal in a layerl of say one-half inch thickness, which coal may be deposited directly to the pans 10 through the main feed 17 or may-be preheated before it enters the pans in the main conveyor .b first having travelled the length of the aux' iary conveyor 14 from where itis discharged into the pans of the main conveyor 9. In'other words, the supplemental feed may be used if desirable, but it need not be used if satisfactory conditions can be obtained by depositing the material from the feed 17 directly into the pans of the main conveyor. The pans travel very slowly through the main conveyor, and 1n factjust as soon as each pan passes around the sprocket 8 it receives its fuel charge and it mayrequire approximately' fifteen minutes to mo v e A this chargeto the outlet 13 atpthe opposltefgs'lde of the retort. The hearth 3 is malntained at a comparatively high temperature so as to prevent a sudden coolin ofthe ans when moving above said heart In act, when the pans are at a. temperature of say 7 00 C.

pans may be of a temperature of approximatel 5 C. when passing around the s roc et It will be apparent that during t Iis heat treatment volatiles arebein driven 05 from the coal charge, and these volatiles pass when they move around thesprocket 8 said,

out through the vapor discharge pipe 7. The carbonized residue from each pan is automatically discharged into the opening 13 as the pans pass around the sprocket 7.

It will` be clearly apparent that it is vitalA in this process that the cast iron pans should be of suiiicient size to absorb that amount of heat necessary to distill the volatiles from the coal charges and to convert the residue into coke. The .coal will ordinarily have to be sub'ected to a temperature of not less than 500 to properly cause its distillation and in carryin out this process I therefore utilize pans o sufcient thickness to retain this temperature"- Vwhen'thepans are travelling over the 'hearth 3. By this process the maximum temperature is not applied directly to" the pans vwhile they 'contain the coal undergoing treatment, but the -heat absorbed in the thereto in such quantities that;the coal is carbonized by the contained heat 'f the receptacles, in moving the receptacles with the coal charges through a distilling zone where the volatiles of the coal are removed and a carbonized residue produced without raising alsthe temperature of such receptacles, and in discharging such residue from the receptacles.

2'. A process for carbo-nizin consisting in passing a series of eat storing receptacles through a heating zone, in storing 1n such receptacles suiiicient heat to carl bonize a charge of coal, in introducing charges of coal to such receptacles after their .heat treatment and in moving such receptacles with the1r contained charges through a distilling zone where-the temperature of the receptacles is not raised and Where the .volatiles lare removed 'and a carbonized resi- -due produced by the stored heat ofthe receptacles, and in discharging vsuch residue after the distilling treatment.

3. A continuous carbonizing process, comprising moving a series of heat storing receptacles through a heating zone, in heatin such receptacles while passmg through sai zone' to tempxerature to store in such receptacles s uilicient heat to carbonize fuel charges, in introducing to the heated receptacles fuel chargesto travel therein through a distilling zone where the volatiles of such charges are removed and the carbonized residue produced by the stored heat of said receptacles,

materials,

in discharging the Lcmbonized residue after such treatment, und in collecting vapors produced during the distilling operation.

4. A process for carbonizing coal` consisting in passing heut storing devices through u heating zone Where seid devices are heated to n temperature to store therein sufficient heut to carbonize comminuted coal charges, in movinfr said devices after their heut treatment through a, distlling zone, end in which zone coul charges are applied to seid devices und undergo volntiiizntion during passage through the distilling zone Without substnntinll raising the temperature of seid devices und y reason of the contained heut thereof, und in discharging the curbonized residue after such treatment.

In testimon whereof I affix my signature.

1 ENNETII M. SIMPSON. 

